:root {
  --paper: #fbf7f0;
  --paper-2: #f4ecdf;
  --paper-3: #ece1cf;
  --ink: #262019;
  --ink-soft: #5c5346;
  --ink-faint: #8a7f6e;
  --accent: #e68a3c;
  --accent-2: #c96f22;
  --accent-soft: rgba(230, 138, 60, .12);
  --green: #3f6f4e;
  --line: #e6dccb;
  --line-strong: #d6c9b2;
  --code-bg: #2a241c;
  --shadow: 0 1px 0 rgba(0,0,0,.04), 0 18px 40px -28px rgba(60,40,15,.45);
}
* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  background: var(--paper);
  color: var(--ink);
  font-family: "Spline Sans", system-ui, sans-serif;
  font-size: 17px;
  line-height: 1.68;
  -webkit-font-smoothing: antialiased;
  min-height: 100vh;
  background-image:
    radial-gradient(circle at 15% 8%, rgba(230,138,60,.07), transparent 42%),
    radial-gradient(circle at 85% 30%, rgba(63,111,78,.05), transparent 40%);
}
a { color: var(--accent-2); }
a:focus-visible, button:focus-visible, input:focus-visible {
  outline: 3px solid var(--accent);
  outline-offset: 2px;
  border-radius: 4px;
}
.skip-link {
  position: absolute; left: -9999px; top: 0;
  background: var(--ink); color: var(--paper);
  padding: .6rem 1rem; z-index: 100; border-radius: 0 0 8px 0;
}
.skip-link:focus { left: 0; }

/* Top bar */
.topbar {
  position: sticky; top: 0; z-index: 50;
  background: rgba(251,247,240,.9);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--line);
}
.topbar-inner {
  max-width: 1000px; margin: 0 auto; padding: .8rem clamp(20px,5vw,48px);
  display: flex; align-items: center; justify-content: space-between; gap: 12px;
}
.brand { font-family: "Fraunces", serif; font-weight: 700; font-size: 1.05rem; color: var(--ink); text-decoration: none; letter-spacing: -.01em; }
.brand em { font-style: italic; color: var(--accent-2); }
.series-link {
  font-family: "JetBrains Mono", monospace; font-size: 11px; letter-spacing: .12em;
  text-transform: uppercase; color: var(--ink-soft); text-decoration: none;
  border: 1px solid var(--line-strong); border-radius: 999px; padding: .35rem .8rem;
  transition: all .2s;
}
.series-link:hover { border-color: var(--accent); color: var(--accent-2); }

/* Hero */
.hero { max-width: 1000px; margin: 0 auto; padding: clamp(40px,7vw,72px) clamp(20px,5vw,48px) 0; }
.eyebrow {
  font-family: "JetBrains Mono", monospace; font-size: 11px; letter-spacing: .34em;
  text-transform: uppercase; color: var(--accent-2); font-weight: 600;
}
h1.title {
  font-family: "Fraunces", serif; font-weight: 900;
  font-size: clamp(40px, 6.5vw, 72px); line-height: .98; letter-spacing: -.02em;
  margin: 16px 0 0;
}
h1.title em { font-style: italic; font-weight: 600; color: var(--accent-2); }
.lede { font-size: clamp(18px, 2.2vw, 21px); line-height: 1.6; color: var(--ink-soft); max-width: 640px; margin: 22px 0 0; }
.hero-grid { display: grid; grid-template-columns: 1.05fr .95fr; gap: clamp(24px,4vw,48px); align-items: center; margin-top: 8px; }
.hero-figure { margin: 0; }
.hero-figure img {
  width: 100%; height: auto; border-radius: 18px;
  border: 1px solid var(--line); box-shadow: var(--shadow);
  display: block;
}
.hero-figure figcaption {
  font-family: "JetBrains Mono", monospace; font-size: 11px; letter-spacing: .08em;
  color: var(--ink-faint); margin-top: .6rem; text-align: center;
}

.stats { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 30px; align-items: center; }
.stat {
  font-family: "JetBrains Mono", monospace; font-size: 12px; color: var(--ink-soft);
  border: 1px solid var(--line-strong); border-radius: 40px; padding: 7px 16px;
  background: rgba(255,255,255,.4);
}
.stat b { color: var(--accent-2); font-weight: 600; }
.progress-pill { font-family: "JetBrains Mono", monospace; font-size: 12px; color: var(--ink-soft); border: 1px solid var(--line-strong); border-radius: 40px; padding: 7px 16px; background: rgba(255,255,255,.4); }
.progress-pill b { color: var(--accent-2); font-weight: 600; }
.progress-pill.done-all { border-color: var(--green); color: var(--green); }
.progress-pill.done-all b { color: var(--green); }

.cta-row { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 26px; }
.btn {
  display: inline-flex; align-items: center; gap: 8px;
  font-family: "Spline Sans", sans-serif; font-weight: 600; font-size: 15px;
  text-decoration: none; border-radius: 12px; padding: .8rem 1.3rem;
  transition: all .2s; cursor: pointer; border: 1px solid transparent;
}
.btn-primary { background: var(--accent); color: #fff; box-shadow: 0 8px 20px -10px var(--accent); }
.btn-primary:hover { background: var(--accent-2); }
.btn-ghost { background: transparent; color: var(--ink); border-color: var(--line-strong); }
.btn-ghost:hover { border-color: var(--accent); color: var(--accent-2); }
.btn .kbd {
  font-family: "JetBrains Mono", monospace; font-size: 11px; background: rgba(255,255,255,.25);
  border-radius: 5px; padding: .1rem .4rem; border: 1px solid rgba(255,255,255,.35);
}
.btn-ghost .kbd { background: var(--paper-2); border-color: var(--line-strong); color: var(--ink-faint); }

.hr-accent { height: 2px; width: 120px; background: var(--accent); margin: 48px 0 0; }

/* Chapters */
.chapters-wrap { max-width: 1000px; margin: 0 auto; padding: 0 clamp(20px,5vw,48px) 40px; }
.section-head { display: flex; align-items: baseline; justify-content: space-between; gap: 16px; margin: 56px 0 6px; }
.section-head h2 { font-family: "Fraunces", serif; font-weight: 700; font-size: clamp(26px,3.5vw,34px); letter-spacing: -.01em; }
.section-head .sub { font-family: "JetBrains Mono", monospace; font-size: 11px; letter-spacing: .2em; text-transform: uppercase; color: var(--ink-faint); }
.chapters { display: flex; flex-direction: column; gap: 10px; margin-top: 20px; }

.chapter-row { display: flex; gap: 10px; align-items: stretch; }
.ch-done-btn {
  flex: none; width: 46px; border-radius: 12px; border: 1px solid var(--line-strong);
  background: rgba(255,255,255,.4); cursor: pointer; display: flex; align-items: center; justify-content: center;
  transition: all .2s; color: transparent;
}
.ch-done-btn:hover { border-color: var(--accent); }
.ch-done-btn .check-svg { width: 18px; height: 18px; }
.ch-done-btn.done { background: var(--green); border-color: var(--green); color: #fff; }
.chapter-card {
  flex: 1; display: flex; align-items: center; gap: 18px; text-decoration: none; color: var(--ink);
  padding: 18px 22px; border: 1px solid var(--line); border-radius: 14px;
  background: rgba(255,255,255,.45); transition: all .22s ease; box-shadow: 0 2px 8px -6px rgba(60,40,15,.1);
}
.chapter-card:hover { border-color: var(--accent); background: rgba(255,255,255,.75); transform: translateX(5px); box-shadow: var(--shadow); }
.chapter-card:hover .card-num { background: var(--accent); color: #fff; box-shadow: 0 6px 14px -8px var(--accent); }
.card-num {
  font-family: "JetBrains Mono", monospace; font-weight: 700; font-size: 13px; color: var(--accent-2);
  background: var(--accent-soft); border-radius: 10px; width: 44px; height: 44px;
  display: flex; align-items: center; justify-content: center; flex: none; transition: all .22s;
}
.card-info { min-width: 0; }
.card-title { font-family: "Fraunces", serif; font-weight: 600; font-size: 18px; letter-spacing: -.01em; line-height: 1.2; }
.card-desc { font-size: 14px; color: var(--ink-soft); margin-top: 3px; line-height: 1.5; }
.card-arrow { margin-left: auto; color: var(--line-strong); flex: none; transition: color .2s; }
.chapter-card:hover .card-arrow { color: var(--accent); }

/* How to read */
.howto { max-width: 1000px; margin: 0 auto; padding: 0 clamp(20px,5vw,48px) 20px; }
.howto-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 16px; margin-top: 20px; }
.howto-card { border: 1px solid var(--line); border-radius: 14px; padding: 20px; background: rgba(255,255,255,.4); }
.howto-card .n { font-family: "JetBrains Mono", monospace; font-size: 12px; color: var(--accent-2); font-weight: 700; }
.howto-card h3 { font-family: "Fraunces", serif; font-size: 17px; margin: 6px 0 6px; }
.howto-card p { font-size: 14px; color: var(--ink-soft); line-height: 1.55; }

/* Footer */
footer.doc { max-width: 1000px; margin: 0 auto; padding: 0 clamp(20px,5vw,48px) 80px; }
footer.doc .inner { border-top: 2px solid var(--accent); padding-top: 28px; margin-top: 40px; }
footer.doc .big { font-family: "Fraunces", serif; font-style: italic; font-size: 24px; color: var(--ink); margin-bottom: 8px; }
footer.doc p { font-size: 14px; color: var(--ink-soft); }

/* Search modal */
.search-overlay {
  position: fixed; inset: 0; background: rgba(38,32,25,.5); z-index: 200;
  display: none; align-items: flex-start; justify-content: center; padding: 12vh 20px 20px;
}
.search-overlay.open { display: flex; }
.search-modal {
  width: 100%; max-width: 560px; background: var(--paper); border-radius: 16px;
  box-shadow: 0 30px 80px -20px rgba(0,0,0,.4); overflow: hidden;
  border: 1px solid var(--line-strong);
}
.search-input-wrap { display: flex; align-items: center; gap: 12px; padding: 16px 18px; border-bottom: 1px solid var(--line); }
.search-input-wrap svg { color: var(--ink-faint); flex: none; }
.search-input {
  flex: 1; border: none; background: transparent; font-family: "Spline Sans", sans-serif;
  font-size: 17px; color: var(--ink); outline: none;
}
.search-input::placeholder { color: var(--ink-faint); }
.search-kbd {
  font-family: "JetBrains Mono", monospace; font-size: 11px; color: var(--ink-faint);
  border: 1px solid var(--line-strong); border-radius: 5px; padding: .1rem .45rem; flex: none;
}
.search-results { max-height: 46vh; overflow-y: auto; padding: 8px; }
.search-result {
  display: flex; align-items: center; gap: 12px; text-decoration: none; color: var(--ink);
  padding: 12px 14px; border-radius: 10px; transition: background .15s;
}
.search-result:hover, .search-result.active { background: var(--paper-2); }
.sr-num { font-family: "JetBrains Mono", monospace; font-size: 12px; color: var(--accent-2); font-weight: 700; flex: none; width: 30px; }
.sr-title { font-family: "Fraunces", serif; font-weight: 600; font-size: 16px; }
.sr-meta { margin-left: auto; font-size: 12px; color: var(--ink-faint); flex: none; }
.search-no-results { padding: 20px; text-align: center; color: var(--ink-soft); font-size: 15px; }

/* Responsive */
@media (max-width: 760px) {
  .hero-grid { grid-template-columns: 1fr; }
  .hero-figure { order: -1; }
  .chapter-card { padding: 14px 16px; gap: 12px; }
  .card-title { font-size: 16px; }
  .card-desc { font-size: 13px; }
  .card-num { width: 36px; height: 36px; font-size: 12px; }
  .ch-done-btn { width: 40px; }
  .section-head { flex-direction: column; gap: 4px; }
}